by Gregg Zoroya, USA TODAY

by Gregg Zoroya, USA TODAY

Opponents of the death penalty say the agonizing death of an Oklahoma inmate from lethal injection this week will further slow the pace of executions in America, adding weight to courtroom arguments against it.

Clayton Lockett, 38, struggled violently, groaned and writhed after drugs were administered by Oklahoma officials Tuesday night, eyewitnesses say. He lifted his head and shoulders as if struggling to sit up on a gurney, fighting against restraints, according to an eyewitness account in the Tulsa World.

But proponents of the death penalty are quick to argue that most Americans continue to support it, and that while Lockett's death could be a powerful emotional lever for those in opposition, courts will not necessarily be swayed to stay more executions.

Lockett was convicted of shooting a 19-year-old woman and watching two accomplices bury her alive in 1999. Oklahoma had two executions set for Tuesday night. The second was delayed by Gov. Mary Fallin for two weeks pending a review of Lockett's death.

"I believe the death penalty is an appropriate response and punishment to those who commit heinous crimes against their fellow men and women," Fallin said. "However, I also believe the state needs to be certain of its protocols and its procedures for executions and that they work."

"We have to stop executions until there's been a full investigation, independent investigation and full transparency," says defense lawyer Madeline Cohen, who represents the condemned prisoner whose execution was delayed by Fallin.

Richard Dieter, executive director of the non-profit Death Penalty Information Center, an opponent of executions, said Lockett's manner of death would add momentum to efforts to halt lethal injection until the process is better understood and there is more transparency in states' procedures.

"Somebody died because of the state's incompetency," Dieter says, adding that Louisiana, Kentucky and Ohio are considering similar protocols. "I think they're going to have second thoughts and those executions will be delayed."

Joshua Marquis, a county prosecutor in Oregon and member of the board of directors of the National District Attorneys Association, says it's possible that governors already considering suspending executions â?? as has happened recently in Washington, Colorado and Oregon â?? may use the death of Lockett as an "excuse" to do so going forward. But he does not believe that judges â?? particularly in the conservative states where executions are currently pending such as Texas and Ohio -- will be more inclined to grant stays of execution because of it.

Executions have been on the decline, dropping from 98 in 1999 to 39 last year. The only lethal injections currently scheduled over the next four months are four in May -- one each in Oklahoma, Missouri, Texas and Ohio. There have 17 executions so far this year, including Locketts'.

Marquis and other death penalty proponents say lethal injection is still viewed as the most humane process for the condemned.

"I certainly don't believe we ought to be tormenting them or torturing them," Marquis says."But the fact that they don't all come off seamlessly does not mean that we have a tremendous crisis with the death penalty."

Death penalty states have been struggling in recent years to carry out executions because of a shortage of commonly used drugs, largely because of decisions by manufacturers in Europe to block their use on condemned prisoners.

The result has been a scramble to obtain necessary narcotics. States often rely on compounding pharmacies that can make drugs to order. Many of these pharmacies, however, stop cooperating when their efforts are publicized.

This has led to legal battles between death penalty states and lawyers for condemned prisoners over how much of the death penalty process can remain secret.

States have begun to keep secret about where drugs are obtained. Correction officials such as those in Oklahoma have turned to lethal injection protocols never before used in executions.

The process Oklahoma used Tuesday night involved administering midazolam, an anti-seizure medication, as an anesthetic before paralyzing Lockett with vecuronium bromide and then injecting him with potassium chloride to stop his heart.

Midazolam and vecuronium bromide have been in short supply. But Oklahoma recently informed lawyers for Lockett and Warner that commercially manufactured quantities had been located, although the state refuses to provide more information.

Defense lawyers said the amount of midazolam set for use on Lockett and Warner was one-fifth what had been used on a previous Florida execution, the only other time this three-drug combination had been used.

Defense attorneys say their fear is that the drug used as an anesthetic will not work properly, leaving the condemned to suffer in agony from the next two drugs administered.

"There's no dispute that potassium chloride (used to stop the heart) is excruciatingly painful," Cohen says. "So the problem is when the first drug doesn't work, the second drug (the paralytic vecuronium bromide) causes a horrible suffocating .. and the third drug scores the veins and causes a terribly painful, horrible heart attack."

The ACLU of Oklahoma issued a statement decrying the death of Lockett as a "hastily thrown together human science experiment" and it called for greater transparency for a process it said has fundamentally failed.

Attorneys for Lockett and Warner had successfully won a stay of execution for both men from a state district judge on March 26. The judge ruled that Oklahoma's secrecy statute for executions was unconstitutional.

The state's Supreme Court later ruled 5-4 to extend the stay.

But that high court reversed itself April 23, clearing the way for the scheduled double execution.

Lockett's death is at least the fourth lethal injection death in recent years where witnesses reported condemned prisoners in agony. Previous cases included:

â?¢ The Jan. 16 execution of Dennis McGuire in Ohio during which he appeared to struggle and gasp for 20 minutes before dying;

â?¢ The 2012 execution in South Dakota of Eric Robert who witnesses said appeared to clear his throat and gasp, his skin turning purplish and his eyes remaining open until he died.

"To get these drugs (executioners) are turning to really, really shady methods of obtaining them that leads to potential contamination, adulteration, expiration," says Cohen, Warner's lawyer. "I can't believe we're still having this fight (over lethal injection) in the wake of this horrible, horrible event."